Guidelines recommended by the Sri Lanka College of Paediatricians, November 2014

Based on the European Society for Paediatric Endocrinology – Consensus Guidelines on Screening, Diagnosis and Management of Congenital Hypothyroidism (J Clin Endocrinol Metab 2014; 99(2):363-84

Early detection and treatment of congenital hypothyroidism (CH) prevents neuro-developmental disability and optimizes growth and development.
All babies should be screened for congenital hypothyroidism.
Congenital hypothyroidism should be managed by a Paediatrician or a Paediatric Endocrinologist.

  1. Neonatal screening for CH
  • All babies should have a heel prick blood screening test for TSH before discharge from the institution at which the birth took place
  • Abnormal heel prick results should be notified over the phone to the parents and the relevant Paediatrician
    Cord blood analysis –

Parents/paediatrician should be notified when the TSH level is over 20mU/L.

  • If cord blood TSH is over 20 mU/L – perform a venous free thyroxine (fT4) and TSH between day 3 and day 5 for confirmation.
  • Preterm neonates, low-birth weight (LBW) and very low-birth weight (VLBW) neonates, and ill, preterm neonates admitted to neonatal intensive care units (NICU) should have their screening either before discharge or before 4 weeks of age, whichever comes earlier.
  • Neonates treated with Dopamine or Dobutamine should have their screening test two (2) weeks after stopping Dopamine/Dobutamine.
  1. Biochemical criteria used in the decision to initiate treatment
  • If capillary TSH concentration on neonatal screening is ³ 40 mU/L perform a TSH and fT4 (TFT) on venous blood and start treatment.

If results could be obtained on the same day, treatment can be withheld till then.

  • If capillary TSH concentration is less than 40 mU/L, repeat a venous TFT. Treatment can be withheld till the venous TFT results are available, provided these will be available on the following day.
  1. Decision to start treatment based on the venous TFTs
  • If venous free T4 (fT4) concentration is below the normal range for age, treatment should be started immediately.
  • If venous TSH concentration is greater than 20 mU/L, treatment should be started, even if fT4 concentration is normal.
  • If venous TSH concentration is ³ 6 to 20 mU/L after 21 days in a well baby with a fT4 concentration within the normal range for age –
    • Repeat TFT in 2 weeks
    • Perform an ultrasound scan (USS) of the thyroid gland
    • If a small/ectopic thyroid gland is seen with a TSH ³ 6 to 20 mU/L, then, irrespective of the fT4 value, thyroxine therapy should be started
    • If the thyroid gland is normal on USS with a TSH ³ 6 to 20 mU/L with a normal fT4, repeat TFTs, every two weeks till TSH normalizes
  1. Imaging
  • All children with congenital hypothyroidism should have an USS of the thyroid gland.
  • If facilities are available it is recommended to perform radioisotope scanning before starting treatment or within 3 days of starting treatment.
  • This is not mandatory if facilities are not available.
  • Initiation of treatment should never be delayed pending imaging.
  1. Treatment and monitoring of CH
  • Levo thyroxine (L-T4) is the medication of choice.
  • L-T4 treatment should be initiated as soon as possible and during the first 2 weeks after birth or immediately after confirmatory serum test results are available.
  • Initial dose of L-T4: 10–15 mg/kg per day.
  • Thyroxine should be given early morning on an empty stomach and the breast milk, breakfast or bed tea should be withheld for 30-45 minutes after the medication is administered.
  • L-T4 tablet should be crushed and given dissolved in a few millilitres of breast milk or water.
  • Parents should be provided with written instructions regarding L-T4 treatment.
  1. Monitoring of dose and follow-up
  • Serum or plasma fT4 and TSH concentrations should be determined between 8-9 am before the morning dose of L-T4.
  • First follow up visit – fT4 should be checked 2 weeks after starting thyroxine and adjust the dose accordingly.
  • fT4 concentration should be maintained in the upper half of the age specific reference range.
  • TSH should be maintained in the age specific reference range.

Any reduction of L-T4 dose should not be based on a single increase in fT4 concentration during treatment.
Once TSH/fT4 levels have normalized the suggested follow up is as follows –

During first 6 months of life ® fT4 and TSH should be checked every 6 weeks

6 months to 12 months of life ® fT4 and TSH should be checked every 8 weeks

1 year to 3 years of life ® fT4 and TSH should be checked every 3 months

After 3 years till growth is completed ® fT4 and TSH should be checked every 6-12 months.

  • Additional evaluations should be carried out 4–6 weeks after any change in L-T4 dose.
  • Adequate treatment throughout childhood is essential for normal growth and development.
  • Over-treatment should be avoided.
  • Anthropometry including skull circumference (OFC) measurements and development should be monitored at each clinic visit.
  1. Thyroid re-evaluation

Thyroid re-evaluation should be considered in the following groups of patients

  • Those who had initial TSH > 20 mU/L with normal fT4 and normal USS.
  • All preterm and sick babies who required treatment.
  • Those who had normal TSH levels immediately after commencing treatment.

In these patients treatment should be continued till 3 years of age with regular clinical and biochemical monitoring.

In general, transient hypothyroidism is characterized by a marginally elevated TSH on repeated testing, slightly low or normal fT4 and a low dose of L-T4 is required to maintain euthyroid status.

Thereafter suggested procedure for re-evaluation is:-

  • Reduce dose of L-T4 by 30% for 2 to 3 weeks
  • Check TSH/fT4
  • Repeat an USS of the thyroid gland
  • If TSH > 10mU/L ® congenital hypothyroidism (CH) is confirmed and treatment needs to be continued
  • If CH is not confirmed – Reduce L-T4 dose gradually with repeat TFTs performed 2 to 3 weekly and stop treatment thereafter
  • Repeat a TFT after 3 months of stopping treatment

References

Léger Juliane, Olivieri Antonella, Donaldson Malcolm, Torresani Toni, Krude Heiko, van Vliet Guy, Polak Michel, Butler Gary. European Society for Paediatric Endocrinology – Consensus Guidelines on Screening, Diagnosis and Management of Congenital Hypothyroidism. J Clin Endocrinol Metab 2014;99(2):363-84
Rose Susan R. Update on Newborn Screening and Therapy for Congenital Hypothyroidism. Pediatrics 2006;117(6):2290-2303

Committee appointed by the SLCP to formulate the above guidelines –

Prof. Shamya de Silva (Chairperson)
Dr. Padmakanthi Wijesuriya
Dr. Lilanthi de Silva
Dr. Ramya de Silva
Prof. Sujeewa Amarasena
Dr. Samantha Waidyanatha
Dr. Navoda Atapattu (Convenor)